Design Dropbox / Google Drive
Design a file storage and sync service like Dropbox or Google Drive. This problem tests your ability to handle large […]
System Design
System Design
Design a Web Crawler
Design a web crawler that can index a significant portion of the internet. This question tests whether you understand distributed
AI/ML Interview Questions
How Backpropagation Works: The Chain Rule in Neural Networks
Backpropagation is the algorithm that makes training deep neural networks possible. Every interviewer for ML engineering or research roles expects
System Design
System Design: Ride-Sharing App (Uber / Lyft)
Designing a ride-sharing app is a rich system design problem that tests your ability to handle real-time location data, geospatial
System Design
System Design: Notification System (Push, Email, SMS)
A notification system is asked at almost every senior system design interview because it surfaces real architectural challenges: fanout at
System Design
System Design: Search Autocomplete (Google Typeahead)
Search autocomplete — the suggestions that appear as you type into Google, Amazon, or YouTube — is a deceptively interesting
AI/ML Interview Questions
Overfitting and Regularization: L1, L2, Dropout, and Early Stopping
Overfitting is the most common failure mode in machine learning. Every ML interview will test your ability to recognize it
System Design
System Design: YouTube / Video Streaming Platform
Video streaming is one of the most infrastructure-intensive system design problems. YouTube streams 1 billion hours of video per day.
System Design
System Design: Chat System (WhatsApp / Messenger Scale)
A chat system is a perennial system design interview question. It requires you to reason about real-time communication, persistent storage,
System Design
System Design: Twitter / Social Media Feed
Designing a social media feed is one of the most nuanced system design problems you’ll encounter in interviews. It looks
AI/ML Interview Questions
Bias-Variance Tradeoff: Underfitting, Overfitting, and How to Fix Both
The bias-variance tradeoff is one of the first concepts asked in any machine learning interview. It underpins model selection, regularization,
System Design
System Design: URL Shortener (TinyURL / bit.ly)
Designing a URL shortener is one of the most common system design interview questions, especially at the intern and new
System Design
SQL vs NoSQL: How to Choose the Right Database
“Which database would you use?” is one of the most common follow-up questions in system design interviews. Many candidates default
System Design
API Design: REST vs GraphQL vs gRPC
Every system you design needs an API. In system design interviews, choosing the right API style — and explaining why
AI/ML Interview Questions
Gradient Descent Explained: SGD, Adam, and When to Use Each
Gradient descent is the engine behind nearly every machine learning model trained today. If you are interviewing for an ML